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Australian Institute for Innovative Materials - Papers

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Full-Text Articles in Engineering

Effect Of Alf3-Coated Li4ti5o12 On The Performance And Function Of The Lini0.5mn1.5o4||Li4ti5o12 Full Battery-An In-Operando Neutron Powder Diffraction Study, Gemeng Liang, Anoop Somanathan Pillai Sushamakumari Amma, Vanessa K. Peterson, Kuan-Yu Ko, Chia-Ming Chang, Cheng-Zhang Lu, Chia-Erh Liu, Shih-Chieh Liao, Jin-Ming Chen, Zaiping Guo, Wei Kong Pang Jan 2018

Effect Of Alf3-Coated Li4ti5o12 On The Performance And Function Of The Lini0.5mn1.5o4||Li4ti5o12 Full Battery-An In-Operando Neutron Powder Diffraction Study, Gemeng Liang, Anoop Somanathan Pillai Sushamakumari Amma, Vanessa K. Peterson, Kuan-Yu Ko, Chia-Ming Chang, Cheng-Zhang Lu, Chia-Erh Liu, Shih-Chieh Liao, Jin-Ming Chen, Zaiping Guo, Wei Kong Pang

Australian Institute for Innovative Materials - Papers

The LiNi0.5Mn1.5O4||Li4Ti5O12(LMNO||LTO) battery possesses a relatively-high energy density and cycle performance, with further enhancement possible by application of an AlF3coating on the LTO electrode particles. We measure the performance enhancement to the LMNO||LTO battery achieved by a AlF3coating on the LTO particles through electrochemical testing and use in-operando neutron powder diffraction to study the changes to the evolution of the bulk crystal structure during battery cycling. We find that the AlF3coating along with parasitic Al doping slightly increases capacity and greatly increases rate capability of the LTO electrode, as well as significantly reducing capacity loss on cycling, facilitating a gradual …


Interfacial Contributions To Anomalous Hall Effect In Perpendicular Magnetic Anisotropic [Co2mnsi/Pd]3 Multilayer, Huarui Fu, Caiyin You, Li Ma, Na Tian, Fangqing Xin, Zhenxiang Cheng, Adham Basha, Amit Kohn Jan 2018

Interfacial Contributions To Anomalous Hall Effect In Perpendicular Magnetic Anisotropic [Co2mnsi/Pd]3 Multilayer, Huarui Fu, Caiyin You, Li Ma, Na Tian, Fangqing Xin, Zhenxiang Cheng, Adham Basha, Amit Kohn

Australian Institute for Innovative Materials - Papers

Through engineering the interface between Co2MnSi and Pd, we realize a high perpendicular magnetic anisotropy (PMA) and controllable anomalous Hall effect (AHE) in [Co2MnSi(tCMS)/Pd]3multilayers. The multilayers are characterized by a particulatelike layer morphology following annealing at 573 K with weak B2 crystallographic ordering of the Co2MnSi layer. The largest PMA (Keff) of 1.2x106erg/cm3 has been obtained in [Co2MnSi(1.2nm)/Pd]3 multilayer annealed at 573 K. The AHE can be tuned, which we attribute to a varying proximity effect at the Co2MnSi/Pd interface, by varying the annealing temperature and Co2MnSi thickness. According to the expanded AHE scaling relation, we calculate the different contributions …


Effect Of Storage Environment On Hydrogen Generation By The Reaction Of Al With Water, Yin-Qiang Wang, Wei-Zhuo Gai, Xia-Yu Zhang, Hong-Yi Pan, Zhenxiang Cheng, Pingguang Xu, Zhen-Yan Deng Jan 2017

Effect Of Storage Environment On Hydrogen Generation By The Reaction Of Al With Water, Yin-Qiang Wang, Wei-Zhuo Gai, Xia-Yu Zhang, Hong-Yi Pan, Zhenxiang Cheng, Pingguang Xu, Zhen-Yan Deng

Australian Institute for Innovative Materials - Papers

Al powder was stored in saturated water vapor, oxygen, nitrogen and drying air separately for a time period of up to six months, the degradation behavior of Al activity was characterized by the reaction of Al with water. It was found that water vapor decreased the induction time for the beginning of Al-water reaction and reduced the total hydrogen generation per unit weight of Al, while oxygen increased the induction time and retarded the Al-water reaction. In contrast, the effect of nitrogen and drying air on Al activity was weak. The mechanism analyses indicated that water vapor promoted the hydration …


Photosensitization Of Tio2 Nanofibers By Ag2s With The Synergistic Effect Of Excess Surface Ti3+ States For Enhanced Photocatalytic Activity Under Simulated Sunlight, Samina Ghafoor, Sadia Ata, Nasir Mahmood, Salman Noshear Arshad Jan 2017

Photosensitization Of Tio2 Nanofibers By Ag2s With The Synergistic Effect Of Excess Surface Ti3+ States For Enhanced Photocatalytic Activity Under Simulated Sunlight, Samina Ghafoor, Sadia Ata, Nasir Mahmood, Salman Noshear Arshad

Australian Institute for Innovative Materials - Papers

No abstract provided.


Vibration Effect On Magnetization And Critical Current Density Of Superconductors, Igor A. Golovchanskiy, Alexey V. Pan, Jonathan George, Frederick Wells, Sergey Fedoseev, Anatoly B. Rosenfeld Jan 2016

Vibration Effect On Magnetization And Critical Current Density Of Superconductors, Igor A. Golovchanskiy, Alexey V. Pan, Jonathan George, Frederick Wells, Sergey Fedoseev, Anatoly B. Rosenfeld

Australian Institute for Innovative Materials - Papers

In this work the effect of vibrations on critical current density ( Jc) of superconductors has been studied. The vibrations are shown to affect Jc of all types of superconductors during their measurements, employing a vibrating sample magnetometer (VSM). Increasing vibration frequency ( f ) and/or amplitude (A) leads to progressive reduction of Jc as a function of magnetic field (Ba). The effect of vibrations is substantially stronger in thin films. It leads to development of unexpected kinks on Jc (Ba) curves. Analysis of magnetization loops and relaxation of magnetization in YBCO films revealed that the vibration effect can be …


Systematic Elongation Of Thienyl Linkers And Their Effect On Optical And Electrochemical Properties In Carbazole-Bodipy Donor-Acceptor Systems, Alina Brzeczek, Katarzyna Piwowar, Wojciech Domagala, Mikotaj M. Mikotajczyk, Krzysztof Walczak, Pawel W. Wagner Jan 2016

Systematic Elongation Of Thienyl Linkers And Their Effect On Optical And Electrochemical Properties In Carbazole-Bodipy Donor-Acceptor Systems, Alina Brzeczek, Katarzyna Piwowar, Wojciech Domagala, Mikotaj M. Mikotajczyk, Krzysztof Walczak, Pawel W. Wagner

Australian Institute for Innovative Materials - Papers

Synthesis, spectral and electrochemical properties of a series of new panchromatic BODIPY donor-acceptor-donor derivatives, comprising carbazole conjugated with systematically elongated framework by thiophene-based linkers were investigated. It has been found that elongation of the π-system with one thiophene unit shifts the spectra toward near infrared, while incorporation of next thiophene derivatives has only limited influence on the lowest energy transition, causing no further shift of absorption maxima. Elongation of π-conjugation of the donor arm tunes the electron properties, influencing the ionization potential (IP) and electron affinity (EA) values of the molecules. The experimental results are supported by quantum chemical computations …


Effect Of Tensile Load On The Actuation Performance Of Ph-Sensitive Hydrogels, Sina Naficy, Geoffrey M. Spinks Jan 2015

Effect Of Tensile Load On The Actuation Performance Of Ph-Sensitive Hydrogels, Sina Naficy, Geoffrey M. Spinks

Australian Institute for Innovative Materials - Papers

pH-responsive hydrogels are capable of converting chemical energy to mechanical work. To optimize their use as actuators, their response when operating against an external load must be fully characterized. Here, the actuation strain of a model pH-sensitive hydrogel as a function of different constant loads is studied. The experimental actuation strain, produced by switching the pH from 2 to 12, decreases significantly and monotonically with increasing initial tensile load. Two models are developed to predict the actuation strain as a function of applied stress. Simple mechanical models based on the change in hydrogel modulus and cross sectional area due to …


Magnetocaloric Effect And Magnetostructural Coupling In Mn0.92fe0.08coge Compound, Jianli Wang, Precious Shamba, Wayne D. Hutchison, Qinfen Gu, M F. Md Din, Q Y. Ren, Zhenxiang Cheng, Shane J. Kennedy, Stewart J. Campbell, S X. Dou Jan 2015

Magnetocaloric Effect And Magnetostructural Coupling In Mn0.92fe0.08coge Compound, Jianli Wang, Precious Shamba, Wayne D. Hutchison, Qinfen Gu, M F. Md Din, Q Y. Ren, Zhenxiang Cheng, Shane J. Kennedy, Stewart J. Campbell, S X. Dou

Australian Institute for Innovative Materials - Papers

The structural properties of Mn0.92Fe0.08CoGe have been investigated in detail using synchrotron x-ray diffraction in zero and applied pressure (p = 0-10 GPa). A ferromagnetic transition occurs around TC = 300 K and a large magnetic-entropy change −ΔSM = 17.3 J/kg K detected at TC for a field change of ΔB = 5 T. The field dependence of −ΔS M max can be expressed as −ΔS M max ∝ B. At ambient temperature and pressure, Mn0.92Fe0.08CoGe exhibits a co-existence of the orthorhombic TiNiSi-type structure (space group Pnma) and hexagonal …


The Effect Of Symmetry On Resonant And Nonresonant Photoresponses In A Field-Effect Terahertz Detector, J D. Sun, H Qin, Roger A. Lewis, Xiaoyu Yang, Y F. Sun, Zhenpu Zhang, Xianghu Li, Xiaoqin Zhang, Y Cai, D M. Wu, B S. Zhang Jan 2015

The Effect Of Symmetry On Resonant And Nonresonant Photoresponses In A Field-Effect Terahertz Detector, J D. Sun, H Qin, Roger A. Lewis, Xiaoyu Yang, Y F. Sun, Zhenpu Zhang, Xianghu Li, Xiaoqin Zhang, Y Cai, D M. Wu, B S. Zhang

Australian Institute for Innovative Materials - Papers

The effect of the symmetries in the terahertz (THz) field distribution and the field-effect channel on THz photoresponse is examined. Resonant excitation of cavity plasmon modes and nonresonant self-mixing of THz waves are demonstrated in a GaN/AlGaN two-dimensional electron gas with symmetrically designed nanogates, antennas, and filters. We found that the self-mixing signal can be effectively suppressed by the symmetric design and the resonant response benefits from the residual asymmetry. The findings suggest that a single detector may provide both high sensitivity from the self-mixing mechanism and spectral resolution from the resonant response by optimizing the degree of geometrical and/or …


A Class Of Rare Antiferromagnetic Metallic Oxides: Double Perovskite Amn(3)V(4)O(12) (A = Na+, Ca2+, And La3+) And The Site-Selective Doping Effect, Guangbiao Zhang, Yuan Xu Wang, Zhenxiang Cheng, Yuli Yan, Chengxiao Peng, Chao Wang, Shuai Dong Jan 2015

A Class Of Rare Antiferromagnetic Metallic Oxides: Double Perovskite Amn(3)V(4)O(12) (A = Na+, Ca2+, And La3+) And The Site-Selective Doping Effect, Guangbiao Zhang, Yuan Xu Wang, Zhenxiang Cheng, Yuli Yan, Chengxiao Peng, Chao Wang, Shuai Dong

Australian Institute for Innovative Materials - Papers

We have investigated the structural, electronic, and magnetic properties of A-site-ordered double-perovskitestructured oxides, AA'3B4O12 (A = Na, Ca, and La) with Mn and V at A' and B sites, respectively, using firstprinciple calculations based on the density functional theory. Our calculation results show that the antiferromagnetic phase is the ground state for all the compounds. By changing the A-site ions from Na+ to Ca2+ and then to La3+, the transfer of charge between Mn and O ions was changed from 1.56 to 1.55 and then to 1.50, and that between the …


The Effect Of Surface Passivation On The Structure Of Sulphur-Rich Pbs Colloidal Quantum Dots For Photovoltaic Application, Victor Malgras, Andrew Nattestad, Yusuke Yamauchi, S X. Dou, Jung Ho Kim Jan 2015

The Effect Of Surface Passivation On The Structure Of Sulphur-Rich Pbs Colloidal Quantum Dots For Photovoltaic Application, Victor Malgras, Andrew Nattestad, Yusuke Yamauchi, S X. Dou, Jung Ho Kim

Australian Institute for Innovative Materials - Papers

The use of PbS colloidal quantum dots in photovoltaic devices is very promising because of their simple and low cost production processes and their unique properties, such as bandgap tunability and potential multiple exciton generation. Here we report the synthesis of PbS nanocrystals used for application in solar cells. The sulphur-rich nature of their surface appears to be caused by the exposure to ambient conditions. The use of methanol as medium during the ligand exchange process has a crucial role in the removal of native oleate ligands. Without proper ligand exchange, the unpassivated surface is subject to ambient hydroxylation leading …


Pauli-Limited Effect In The Magnetic Phase Diagram Of Fesexte1−X Thin Films, Jincheng Zhuang, Zhen Li, Xun Xu, Li Wang, Wai Kong Yeoh, X Z. Xing, Zhixiang Shi, Xiaolin Wang, Yi Du, S X. Dou Jan 2015

Pauli-Limited Effect In The Magnetic Phase Diagram Of Fesexte1−X Thin Films, Jincheng Zhuang, Zhen Li, Xun Xu, Li Wang, Wai Kong Yeoh, X Z. Xing, Zhixiang Shi, Xiaolin Wang, Yi Du, S X. Dou

Australian Institute for Innovative Materials - Papers

We present a detailed investigation on the doping dependence of the upper critical fieldHc2(T) of FeSexTe1−xthin films (0.18 ≤ x ≤ 0.90) by measuring the electrical resistivity as a function of magnetic field. The Hc2(T) curves exhibit a downturn behavior with decreasing temperature in all the samples, owing to the Pauli-limited effect (spin paramagnetic effect). The Pauli-limited effect on the upper critical field can be monotonically modulated by variation of the Se/Te composition. Our results show that Te-doping induced disorder and excess Fe atoms give rise to enhancement of the Pauli-limited effect.


Magnetic Properties And Magnetocaloric Effect In Layered Ndmn1.9ti0.1si2, M F. Md Din, Jianli Wang, Shane J. Kennedy, Stewart J. Campbell, S X. Dou Jan 2014

Magnetic Properties And Magnetocaloric Effect In Layered Ndmn1.9ti0.1si2, M F. Md Din, Jianli Wang, Shane J. Kennedy, Stewart J. Campbell, S X. Dou

Australian Institute for Innovative Materials - Papers

The structural and magnetic properties of the NdMn1.9Ti0.1Si2 compund have been studied by high-intensity x-ray and high-resolution neutron powder diffraction, specific heat, dc magnetization, and differential scanning calorimetry measurements over the temperature range of 3-450 K. The Curie temperature and Néel temperature of layered NdMn1.9Ti0.1Si2 are indicated as TC ~ 22 K and TN ~ 374 K respectively. The first order magnetic transition from antiferromagnetic [AFil-type] to ferromagnetic [F(Nd)+Fmc] around TC is found in layered NdMn1.9Ti0.1Si2 and is …


The Synergistic Effect Between Wo3 And G-C3n4 Towards Efficient Visible-Light-Driven Photocatalytic Performance, Imran Aslam, Chuanbao Cao, M Tanveer, Waheed S. Khan, Muhammad Nawaz Tahir, Muhammad Abid, Faryal Idrees, Faheem K. Butt, Zulfiqar Ali, Nasir Mahmood Jan 2014

The Synergistic Effect Between Wo3 And G-C3n4 Towards Efficient Visible-Light-Driven Photocatalytic Performance, Imran Aslam, Chuanbao Cao, M Tanveer, Waheed S. Khan, Muhammad Nawaz Tahir, Muhammad Abid, Faryal Idrees, Faheem K. Butt, Zulfiqar Ali, Nasir Mahmood

Australian Institute for Innovative Materials - Papers

We have developed a facile, scaled up, efficient and morphology-based novel WO3-g-C3N4 photocatalyst with different mass ratios of WO3 and g-C3N4. It was used for the photodegradation of rhodamine B (RhB) under visible light irradiation and it showed excellent enhanced photocatalytic efficiency as compared to pure g-C3N4 and WO3. The apparent performance of the composite/hybrid was 3.65 times greater than pure WO3 and 3.72 times greater than pure g-C3N4 respectively, and it was also found to be much higher than the previously reported ones. Furthermore, the optical properties of composite samples were evaluated. The bandgap of composite samples lies in …


Electrostrictive Effect In Ferroelectrics: An Alternative Approach To Improve Piezoelectricity, Fei Li, Li Jin, Zhuo Xu, Shujun Zhang Jan 2014

Electrostrictive Effect In Ferroelectrics: An Alternative Approach To Improve Piezoelectricity, Fei Li, Li Jin, Zhuo Xu, Shujun Zhang

Australian Institute for Innovative Materials - Papers

Electrostriction plays an important role in the electromechanical behavior of ferroelectrics and describes a phenomenon in dielectrics where the strain varies proportional to the square of the electric field/polarization. Perovskite ferroelectrics demonstrating high piezoelectric performance, including BaTiO3, Pb(Zr1-xTix)O3, and relaxor-PbTiO3 materials, have been widely used in various electromechanical devices. To improve the piezoelectric activity of these materials, efforts have been focused on the ferroelectric phase transition regions, including shift the composition to the morphotropic phase boundary or shift polymorphic phase transition to room temperature. However, there is not much room left to further enhance the piezoelectric response in perovskite solid …


Magnetic Properties And Magnetocaloric Effect In Layered Ndmn 1.9v0.1si2, M F. Md Din, Jianli Wang, R Zeng, Shane Kennedy, S J. Campbell, S X. Dou Jan 2014

Magnetic Properties And Magnetocaloric Effect In Layered Ndmn 1.9v0.1si2, M F. Md Din, Jianli Wang, R Zeng, Shane Kennedy, S J. Campbell, S X. Dou

Australian Institute for Innovative Materials - Papers

The structural and magnetic properties of the compounds NdMn2-xVxSi2 have been studied by x-ray and high resolution neutron powder diffraction, specific heat, dc magnetization, and differential scanning calorimetry measurements over the temperature range 3-450 K. The Curie temperature and Néel temperature of layered NdMn1.9V0.1Si2 are been indicate at TC ~ 24 K and TN ~ 376 K respectively. The giant magnetocaloric effect (GMCE) around TC is found in layered NdMn1.9V0.1Si2 associated with first order magnetic transition from antiferromagnetic [AFil-type] to ferromagnetic [F(Nd)+Fmc]. This behaviorhas been confirmed as contribution of the magnetostructural coupling by using neutron powder diffraction. The magnetic entropy …


Magnetic Properties And Magnetocaloric Effect Of Ndmn2-Xcuxsi2 Compounds, M F. Md Din, Jianli Wang, M Avdeev, Q F. Gu, R Zeng, S J. Campbell, S J. Kennedy, S X. Dou Jan 2014

Magnetic Properties And Magnetocaloric Effect Of Ndmn2-Xcuxsi2 Compounds, M F. Md Din, Jianli Wang, M Avdeev, Q F. Gu, R Zeng, S J. Campbell, S J. Kennedy, S X. Dou

Australian Institute for Innovative Materials - Papers

Structural and magnetic properties of NdMn2−x Cu xSi2 compounds (x = 0-1.0) have been investigated by high intensity x-ray and resolution neutron diffraction (3-450 K), specific heat, dc magnetization, and differential scanning calorimetry measurements. Substitution of Cu for Mn leads to an increase in the lattice parameter a but a decrease in c at room temperature. Two magnetic phase transitions have been found for NdMn2−x Cu xSi2 compounds with TN for the antiferromagnetic ordering of Mn-sublatttice and TC for the Nd-sublattice ferromagnetic ordering, respectively. TC increases significantly with increasing Cu content from 36 K at x = 0 to 100 …


Magnetism And Magnetocaloric Effect Of Mn0.98fe0.02coge, Q Y. Ren, W D. Hutchison, Jianli Wang, S Munoz Perez, J M. Cadogan, S J. Campbell Jan 2014

Magnetism And Magnetocaloric Effect Of Mn0.98fe0.02coge, Q Y. Ren, W D. Hutchison, Jianli Wang, S Munoz Perez, J M. Cadogan, S J. Campbell

Australian Institute for Innovative Materials - Papers

The crystallographic and magnetic properties of Mn0.98Fe0.02CoGe have been investigated by X-ray diffraction, dc magnetization and neutron diffraction over the temperature range 20-450 K. The temperature dependence of the phase fractions of the orthorhombic and hexagonal phases is described well by a Gaussian distribution. The Mn0.98Fe0.02CoGe sample exhibits a first-order magneto-structural transition centred at TMS ∼ 297 K of FWHM ∼37 K with a magnetic entropy change of −ΔSM = 24(1) J kg−1 K−1 for ΔB = 0-5 T. Neutron diffraction indicates a ferromagnetic orthorhombic structure below TMS with only the Mn carrying magnetic moment (3.98(6) µB) at 20 K. …


Magnetic Transitions And The Magnetocaloric Effect In The Pr 1-Xyxmn2ge2 System, Jianli Wang, S J. Campbell, M F. Md Din, S J. Kennedy, M Hofmann Jan 2014

Magnetic Transitions And The Magnetocaloric Effect In The Pr 1-Xyxmn2ge2 System, Jianli Wang, S J. Campbell, M F. Md Din, S J. Kennedy, M Hofmann

Australian Institute for Innovative Materials - Papers

Layered rare earth compounds in the RMn2X2 series (R = rare-earth; X = Ge, Si) are of interest for potential cooling applications at lower temperatures as they enable the structural and magnetic behavior to be controlled via substitution of R, Mn, and X atoms on the 2a, 4d, and 4e sites respectively. We continue investigations of the Pr1−xYxMn2Ge2 magnetic phase diagram as functions of both composition and Mn-Mn spacing using X-ray and neutron diffraction, magnetization and differential scanning calorimetry measurements. Pr1−xYxMn2Ge2 exhibits an extended region of re-entrant ferromagnetism around x ∼ 0.5 with re-entrant ferromagnetism at inline image for Pr0.5Y0.5Mn2Ge2. …


Electronic Coupling And Catalytic Effect On H2 Evolution Of Mos2/Graphene Nanocatalyst, Ting Liao, Ziqi Sun, Chenghua Sun, S X. Dou, Debra J. Searles Jan 2014

Electronic Coupling And Catalytic Effect On H2 Evolution Of Mos2/Graphene Nanocatalyst, Ting Liao, Ziqi Sun, Chenghua Sun, S X. Dou, Debra J. Searles

Australian Institute for Innovative Materials - Papers

Inorganic nano-graphene hybrid materials that are strongly coupled via chemical bonding usually present superior electrochemical performance. However, how the chemical bond forms and the synergistic catalytic mechanism remain fundamental questions. In this study, the chemical bonding of the MoS 2 nanolayer supported on vacancy mediated graphene and the hydrogen evolution reaction of this nanocatalyst system were investigated. An obvious reduction of the metallic state of the MoS 2 nanolayer is noticed as electrons are transferred to form a strong contact with the reduced graphene support. The missing metallic state associated with the unsaturated atoms at the peripheral sites in turn …


Magnetic Properties And Magnetocaloric Effect Of Ndmn2−Xtixsi2 Compounds, M F. Md Din, Jianli Wang, S J. Campbell, R Zeng, W D. Hutchison, M Avdeev, S J. Kennedy, S X. Dou Oct 2013

Magnetic Properties And Magnetocaloric Effect Of Ndmn2−Xtixsi2 Compounds, M F. Md Din, Jianli Wang, S J. Campbell, R Zeng, W D. Hutchison, M Avdeev, S J. Kennedy, S X. Dou

Australian Institute for Innovative Materials - Papers

The structural and magnetic properties of the intermetallic compounds NdMn2−xTixSi2(x = 0, 0.1, 0.2, and 0.3) have been studied by x-ray and high resolution neutron powder diffraction, specific heat, dc magnetization, and differential scanning calorimetry measurements over the temperature range 3–450 K. The Curie temperature and Néel temperature of NdMn2Si2 decrease from TC = 36 K and TN = 380 K to TC = 14 K and TN = 360 K, respectively, on substitution of Ti (x = 0.3) for Mn. The magnetocaloric effect …


Effect Of Polymer Ligand Structures On Fluorescence Of Gold Clusters Prepared By Photoreduction, Luo Li, Zhen Li, Hui Zhang, Shoucun Zhang, Irfan Majeed, Bien Tan Jan 2013

Effect Of Polymer Ligand Structures On Fluorescence Of Gold Clusters Prepared By Photoreduction, Luo Li, Zhen Li, Hui Zhang, Shoucun Zhang, Irfan Majeed, Bien Tan

Australian Institute for Innovative Materials - Papers

Blue emission fluorescent Au5 clusters with maximum quantum yield of 20.1% were synthesized by a simple photoreduction method using three specially designed tridentate polymer ligands. The evolution of fluorescent Au nanoclusters (Au NCs) under UV irradiation was studied by fluorescence, UV-Vis and X-ray photoelectron spectroscopic techniques, suggesting that the fluorescence of Au NCs is size-dependent and is associated with the presence of Au(i) ions in the Au NCs. The effect of polymer structure on the fluorescent Au NCs has also been discussed. These highly fluorescent Au NCs have potential applications in the fabrication of optoelectronic devices and light emitting materials.


Correlation Between Structural Parameters And The Magnetocaloric Effect In Epitaxial La0.8ca0.2mno3/Laalo3 Thin Film, J C. Debnath, J H. Kim, Y Heo, A M. Strydom, S X. Dou Jan 2013

Correlation Between Structural Parameters And The Magnetocaloric Effect In Epitaxial La0.8ca0.2mno3/Laalo3 Thin Film, J C. Debnath, J H. Kim, Y Heo, A M. Strydom, S X. Dou

Australian Institute for Innovative Materials - Papers

An epitaxial La0.8Ca0.2MnO3/LaAlO 3 (LCMO/LAO) thin film was fabricated using the pulsed laser deposition technique to evaluate the correlation between the crystal structure and the magnetocaloric effect. In our study, the LCMO film was 200 nm in thickness and appeared to have a strong out-of plane texture. We found that each column in the LCMO thin film layer is a domain which has a different ordering direction. These microscopic feature results in anisotropic properties of magnetization, entropy, and relative cooling power. The film exhibited a paramagnetic-to-ferromagnetic second order phase transition at 249 K. The lack of any hysteresis loss also …


Effect Of Sintering Temperature On The Superconducting Properties Of Graphene Doped Mgb2, K S B De Silva, X Xu, Sanjeev Gambhir, D C K Wong, W X Li, Q Y. Hu Jan 2013

Effect Of Sintering Temperature On The Superconducting Properties Of Graphene Doped Mgb2, K S B De Silva, X Xu, Sanjeev Gambhir, D C K Wong, W X Li, Q Y. Hu

Australian Institute for Innovative Materials - Papers

A comprehensive study on the effects of sintering temperature on graphene-doped MgB2 superconductor was conducted. Graphene has emerged as an effective dopant that is capable of improving the critical current density (J-{\rm c}) and flux pinning at a very low doping level, with only a slight reduction of the critical temperature (T-{\rm c}). MgB2 undoped and graphene-doped bulk samples were prepared by the in situ method and sintered within a temperature range from 650 to 950 {\circ}\hbox{C}. It is surprising to note that at the doping level of 1 at.% the sample sintered at 850 {\circ}\hbox{C} shows a J\rm c …


The Effect Of Microscopic Texture On The Direct Plasma Surface Passivation Of Si Solar Cells, S Mehrabian, S Xu, A A. Qaemi, B Shokri, C Chan, K Ostrikov Jan 2013

The Effect Of Microscopic Texture On The Direct Plasma Surface Passivation Of Si Solar Cells, S Mehrabian, S Xu, A A. Qaemi, B Shokri, C Chan, K Ostrikov

Australian Institute for Innovative Materials - Papers

Textured silicon surfaces are widely used in manufacturing of solar cells due to increasing the light absorption probability and also the antireflection properties. However, these Si surfaces have a high density of surface defects that need to be passivated. In this study, the effect of the microscopic surface texture on the plasma surface passivation of solar cells is investigated. The movement of 105Hþ ions in the texture-modified plasma sheath is studied by Monte Carlo numerical simulation. The hydrogen ions are driven by the combined electric field of the plasma sheath and the textured surface. The ion dynamics is simulated, and …


Magnetism And The Magnetocaloric Effect In Prmn1. 6fe0. 4ge2, W D. Hutchison, Jianli Wang, S J. Campbell Jan 2013

Magnetism And The Magnetocaloric Effect In Prmn1. 6fe0. 4ge2, W D. Hutchison, Jianli Wang, S J. Campbell

Australian Institute for Innovative Materials - Papers

The magnetic and magnetocaloric properties of PrMn1.6Fe0.4Ge2around the ferromagnetic transitions T C inter ~ 230 K and T C Pr ~ 30 K have been investigated by magnetisation, 57Fe Mössbauer spectroscopy and electron paramagnetic resonance (EPR) measurements over the temperature range 5–300 K. The broad peaks in magnetic entropy around TC inter (intralayer antiferromagnetism of the Mn sublattice to canted ferromagnetism) and TC Pr (onset of ferromagnetic order of Pr sublattice in addition to ferromagnetically ordered Mn sublattice) are typical of second order transitions with maximum entropy values of -ΔS M ~ 2.0 J/kg K and -ΔS M ~ 2.2 …


Aging Effect Evolution During Ferroelectric-Ferroelectric Phase Transition: A Mechanism Study, Zuyong Feng, Zhenxiang Cheng, Dongqi Shi, S X. Dou Jan 2013

Aging Effect Evolution During Ferroelectric-Ferroelectric Phase Transition: A Mechanism Study, Zuyong Feng, Zhenxiang Cheng, Dongqi Shi, S X. Dou

Australian Institute for Innovative Materials - Papers

Aging can significantly modify the dielectric, piezoelectric, and ferroelectric performance of ferroelectrics. However, little attention has been paid to the aging effect during ferroelectric-ferroelectric phase transitions that is essentially correlated with real applications. In this letter, the authors report the aging effect evolution between two ferroelectric phases in an acceptor-doped piezoceramics. The results show that aging-induced double hysteresis loops were exhibited in different ferroelectric phases, but disappeared during ferroelectric-ferroelectric phase transitions, suggesting the mechanism that the intrinsic restoring force for the reversible switching of domains caused by the alignment of defect dipoles was weakened due to ferroelectric dipole reorientation.


Effect Of Frozen Spin On The Magnetocaloric Property Of La0.7ca0.3coo3 Polycrystalline And Single Crystal Samples, J C. Debnath, R Zeng, J H. Kim, P Shamba, Dapeng Chen, S X. Dou Jan 2012

Effect Of Frozen Spin On The Magnetocaloric Property Of La0.7ca0.3coo3 Polycrystalline And Single Crystal Samples, J C. Debnath, R Zeng, J H. Kim, P Shamba, Dapeng Chen, S X. Dou

Australian Institute for Innovative Materials - Papers

Polycrystalline (PC) and single crystalline (SC) samples of La0.7Ca0.3CoO3 (LCCO) with the perovskite structure were synthesized by conventional solid-state reaction and the floating-zone growth method. We conducted isothermal magnetization measurements of the PC and SC samples at temperatures from 2.8 K to 140 K, and evaluated the magnetic entropy change (−ΔSM) under zero field cooling (ZFC) and field cooling (FC) to 2.8 K. An interesting result has been obtained, where the −ΔSM–T curves in the low temperature range show totally different features between the ZFC and FC cooling procedures. The −ΔS …


Magnetocapacitance Effect In Nonmultiferroic Yfe03 Single Crystal, Z X. Cheng, H Shen, J Xu, Peng Liu, S J. Zhang, Jianli Wang, Xiaolin Wang, S X. Dou Jan 2012

Magnetocapacitance Effect In Nonmultiferroic Yfe03 Single Crystal, Z X. Cheng, H Shen, J Xu, Peng Liu, S J. Zhang, Jianli Wang, Xiaolin Wang, S X. Dou

Australian Institute for Innovative Materials - Papers

YFeO3 single crystal displays two relaxor-like dielectric relaxations, one at low temperature (170300 K) and one at high temperature (370520 K), which are attributed to the activation of electrons and oxygen vacancies, respectively. Above the temperature at which electrons are activated, the sample displays a large magnetocapacitance effect. Comparison of the impedance Cole-Cole plots measured with and without applied magnetic field reveals that the occurrence of magnetocapacitance effect is accompanied with an increasing in DC conductivity under magnetic field after the activation of electrons, which is explained by the enhancement of electron jumping in Fe2b-O-Fe3b chains by magnetic field. Thus …


A Sign Of Field-Induced First Order Magnetic State Transition And Giant Reversible Magnetocaloric Effect In Cobalt Hydroxide Nanosheets, Precious Shamba, Rong Zeng, J Q Wang, S X. Dou Jan 2010

A Sign Of Field-Induced First Order Magnetic State Transition And Giant Reversible Magnetocaloric Effect In Cobalt Hydroxide Nanosheets, Precious Shamba, Rong Zeng, J Q Wang, S X. Dou

Australian Institute for Innovative Materials - Papers

We report the synthesis of β−Co(OH)2 nanosheets using microwave assisted hydrothermal and conventional chemical reaction methods. A magnetic transition at an onset temperature, T1 ~ 96 K, and a sign of antiferromagnetic state transition at the Néel temperature, TN=9~10 K, can be determined from M-T curves and M-H curves magnetic properties investigation. It is found that a sign of field-induced first order transition below 9 K, act as a role of reversing the magnetocaloric effect from negative to positive value. The large reversible magnetic-entropy change (∆SM) of 17 J/kg K around 11 K for …